How to Find and Unlock All Vaults of Forbidden Knowledge in Hell is Us

In Hell is Us, players can find six Vaults of Forbidden Knowledge. Each one is tied to a rather convoluted chain of actions and is ultimately necessary for obtaining numerous items and achievements. In this guide, we will describe the location of each vault and provide the correct combinations to open them.

Vaults of Forbidden Knowledge are locked secret rooms where useful finds are stored. Inside, you can discover glyphs, weapons, relics, and other items that expand the game's lore. The solution to the puzzle that allows you to open each door becomes available only after handing over certain items to Tania for research. The solution is unique for each vault and remains unchanged for every playthrough, so you can safely use this guide to open them all.

In this guide, the vaults are listed in the order they appear in the game, as well as in the Research menu. As the story progresses, you’ll notice that Tania creates the necessary items for analysis in this very order. However, keep in mind: if you open a vault before you receive information about it from Tania, it will not be shown in the Research journal.

From the armored personnel carrier, head up the hill, where you’ll come across a camp you may have already visited at the very beginning of the playthrough. Go around the tent and find the entrance to the cave. Descend there and locate the entrance to the vault.

Here is the correct combination to open the door (left to right):

Inside you will find the following items:

Return to the armored personnel carrier and head east to the main hub. After that, make your way along the cliff—you need to reach the area above the waterfall, where you’ll see stone ruins. Descend to about the middle of the waterfall from the very top ledge to find the entrance to the vault.

Correct combination (left to right):

Upon opening the vault, you will receive:

Once again, return to the armored personnel carrier, but this time take the path down to the lake. Upon reaching the shore, head southeast. There you’ll come across another cave, where the vault door awaits.

Correct combination:

Inside you will find:

The exploration once again starts from the APC. Now you need to head to the excavation site, then descend to its first level. Here you’ll find a round door with a puzzle, behind which is the vault door.

Combination left to right:

Inside you will find:

Return to the starting location and from there head to the ruins area in the southeast. First, go around the ruins and find the cave. Once inside, proceed to the tunnel in the center.

Combination left to right:

Inside you will find:

The last, sixth vault is unlocked with Mystery No.9: Observation Post 08. You need to go northeast from Jova to the OMSIF camp. Once there, go around it and find the cave at the back.

Inside you will find: